Int. J. Curr. Res. Biosci. Plant Biol. 2015, 2(7): 34-37
International Journal of Current Research in
Biosciences and Plant Biology
ISSN: 2349-8080 Volume 2 Number 7 (July-2015) pp. 34-37
www.ijcrbp.com
Original Research Article
A Comparative Histology and Histochemistry of Stomach of Three Teleostean Fishes
B. Laxma Reddy* and G. Benarjee
Fisheries Research Lab, Department of Zoology, Kakatiya University, Warangal-506 009, India
*Corresponding author.
A b s t r a c t
K e y w o r d s
In fresh water teleosts structure of stomach is quite similar to that of oesophagus
except the modifications of the lining of the epithelium into characteristic gastric
epithelium and gastric glands. Stomach is formed by four layers that is mucosa with
superficial epithelium and glandular epithelium, submucosa, muscularis and serosa. In
the present study histomorphological and histochemical changes have been observed in
the stomach of three fresh water teleost fish species, Labeo rohita, Wallago attu and
Clarias batrachus.
Clarias batrachus
Histochemistry
Histomorphology
Labeo rohita
Stomach
Wallago attu
Introduction
Materials and methods
Fish exhibits diverse nature of dietary habits the
histomorphological adaptations of the alimentary canal
to the specific food habit of the species concerned
become inevitable. In fact, each fish species has its own
structural adaptations of the alimentary canal towards
its specific food habit, which vary greatly in regard to the
ratio of animal and plant materials ingested. Fishes are
generally classified as herbivores, carnivores and
omnivores. Some fishes are grouped as specialists like
planktivores, insectivores, sponge feeders, crustacean
feeders, mollusk feeders, algal fish feeders and
piscivores eating flesh form prey, scales and fins. In the
present study an attempt has been made to characterize
comparatively, the histomorphology and histochemistry
of the stomach in three different fishes- herbivorous
Labeo rohita, carnivorous Wallago attu and omnivorous
Clarias batrachus.
For the present investigation fresh water teleosts, Labeo
rohita, Wallago attu, Clarias batrachus were collected
from fishermen at nearby from water tanks and were
sacrificed by cervical dislocation. The stomach was
removed and cut into small pieces then they preserved in
various fixatives i.e., Bouin s, Susa, Carnoy and
Zenker s fluid. After the routine histological preparation
of the tissue, the sections of 5micron thickness were cut
on rotatory microtome. To study the normal histology of
the stomach Heidenhains Azan (Gurr, 1962) stain was
used. Different kinds of histochemical procedures were
also followed to elucidate the chemical nature of
stomach. The presence of carbohydrates, proteins, and
lipids and nucleic acids was determined by using the
technique mentioned by Pearse (1968), Gomorie (1952),
McManus and Mowry (1960), Lillie (1965), Humason
(1967) and Bancroft (1975).
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Int. J. Curr. Res. Biosci. Plant Biol. 2015, 2(7): 34-37
Results and discussion
In the herbivorous Labeo rohita the stomach is not
present. The anterior part of the intestine is known as
intestinal bulb or intestinal swelling. This is a special
feature in these fishes. The intestinal bulb of Labeo
rohita is a thick walled wide structure extending below
the air bladder. It is anterior broader cardiac parts into
which opens dorsally by the pancreatic and bile ducts,
and a posterior narrower pyloric part without pyloric
caeca, which are common in other teleost fishes. In the
carnivorous fish Wallago attu, the oesophagus dilates
into true stomach. It is short pear shaped, thick walled
and secular lies on the ventral side of the airbladder
slightly towards the left side of the visceral cavity. It
consists of three main region, the proximal cardiac,
middle pyloric and the distal blind fundus region. The
structure of the stomach is similar to that of oesophagus,
but the modification of the lining of the stomach into
characteristic gastric epithelium and gastric glands
distinguishes it from the oesophagus, in which the
mucous folds are thin.
The stomach in the omnivorous Clarias batrachus is
demarcated externally from the oesophagus by its large
rounded structure. Stomach is also distinguished from the
oesophagus internally by the differences in the mucosal
folds which are thin in oesophagus and become thicker
and wavy in out line in the stomach. The stomach in this
fish is wider in the middle than at the two ends and looks
like a sac. Its narrow distal end continues into the
intestine and the junction is marked by a distinct
variation. In the present study indicates that stomach is
quite similar to that of oesophagus except the
modifications of the epithelium into characteristic gastric
epithelium and gastric glands. The transition from the
cardiac stomach to the pyloric stomach is gradual. The
mucosal lining of the cardiac stomach is raised into
straight short folds. These folds become thick and
conspicuous in the pyloric region. The stomach of this
fish is also formed by the same layers as found in other
two fishes in the present study. The stomach in fresh
water teleosts exhibits species variation (Sarkar, 1959;
Khanna, 1961; Saxena and Bakshi, 1964; Agarwal and
Sharma, 1966; Dalela, 1969; Moitra and Ray, 1977,
1979; Ray and Moitra, 1982 and Ghosh and Das, 1987).
In the teleostean fishes, a well developed stomach has
formed to receive and store the injested food material.
The structure of the stomach is quite similar to that of
oesophagus except that the epithelial lining of the
stomach has formed into the characteristic gastric
epithelium and gastric glands. The
passing of the
oesophagus into the stomach is recognized by distinct
histological variations. The deep longitudinal folds of the
oesophagus become reduced and gastric glands begin to
appear. This function of oesophagus and stomach is
referred as Oestogaster by Kamal Pasha (1963). It is
formed by four, layers that is mucosa with superficial
epithelium and glandular epithelium, submucosa,
musularis and serosa. The columnar cells of the gastric
epithelium absorptive in function (Greene, 1912; Dawes,
1929; Blake, 1936). The mucous secreting protects the
surface of the stomach from the mechanical injury. The
cells of cardiac region were believed to help in the
digestion of food and the mucous cells of the pyloric
region in the neutralization of the acidity of gastric juice
before it enters in to the intestine.
The histochemical tests conducted on the stomach of
three fishes Labeo rohita, Wallago attu and Clarias
batrachus demonstrated the presence of varied amounts
of carbohydrates, proteins and lipids. The transverse
sections of the stomach of all the three fish species are
depicted in Figs. 1, 2, and 3. The identification of
carbohydrates and carbohydrate containing groups has
made by using the standard technique Periodic acid/
Schiff reaction. The response to PAS reaction in Labeo
rohita was moderate, strong in Wallago attu and in the
case of Clarias batrachus. The striated border of the
stomach was intensively positive while the other layers
are moderately stained. These variations in the intensity
of staining indicated variable concentrations of
carbohydrates in different fishes. The variations in the
amount of carbohydrates are due to the types of the food
fish consumed. In all the three above fishes, other tests
have also been conducted to determine the specificity of
carbohydrate nature, because PAS alone does not
visualize all the carbohydrate groups. The positivity with
PAS may be due to glycogen, free aldehydes and
mucopolysaccharides. Therefore, for the presence of
glycogen in the tissues, PAS/Saliva was used in the
technique. The PAS reaction was found to be resistant to
saliva digestion suggesting the absence of glycogen. The
PAS reaction was blocked in the acetylation solution and
was restored after deacetylation showing the presence of
1 : 2 glycol groups. Similarly PAS alone was employed,
without oxidizing the sections in periodic acid to show
the presence of free aldehydes.
The sections of stomach when subjected to alcian blue at
1.0 PH, the intensity of reaction in Labeo rohita is mild
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Int. J. Curr. Res. Biosci. Plant Biol. 2015, 2(7): 34-37
one, because of the ill developed mucosal folds
containing mucous secreting cells. This further indicates
less quantity of sulfated mucosubstances. But in the case
of Wallago attu, alcian blue at both pH levels responded
suggesting the presence of sulphated mucosubstances,
hyaluronic acid, sialomucins and weak mucosubstances.
The same technique when applied on Clarias batrachus
stomach the intensity was much more, suggesting large
amounts of mucosubstances in the walls of the stomach.
Alcian blue at 2.5pH followed by PAS revealed that the
mucous cells of the stomach in these fishes stained bluish
purple colour indicating the presence of a mixture of
both acid and neutral mucins. The gastric cells were
positive to PAS indicating the occurrence of neutral
mucins.
The PAS positive reaction seen on the surface of the
gastric epithelial cells indicated an absorptive function in
stomach. The reports of other authors (Greene, 1912;
Blake, 1910) indicated that some absorption particularly
of fats occurs in teleostean stomach. The positivity of
PAS also suggests that the occurrence of glycol groups
and aldehydes. The mucoid nature of gastric columnar
cells has been reported for different fish species by
employing histological and histochemicl methods
(Kapoor, 1953; Kamal pasha, 1963; Agarwal and
Sharma, 1966; Tandon and Sharma, 1968; Khanna and
Mehrotra, 1969; Moitra and Ray, 1977 and 1979).
In Labeo rohita the distribution of protein content was
observed uniformly in all the layers of stomach. While
in Wallago attu the muscular and submucosa were more
positive, the gastric glands exhibited little intensity. On
the other hand Clarias batrachus showed that striated
border of the stomach was intensely positive.
However the intensity of reaction varied. The stomach
layers where also positive to Millons reaction and ferric
ferry cyanide suggesting the occurrence of tyrosine
containing proteins and sulfhydryl groups of proteins.
When KMno4/AB was employed the presence of
disulphides was indicated. The occurrence of protein
bound amino groups was found with Ninhydrin/Schiff.
Similarly congored stain demonstrated the presence of
glycoproteins in the stomach of all three species of
fishes.
Fig. 2: T.S. of stomach of Wallago attu.
Fig. 1: T.S. of stomach of Labeo rohita.
Fig. 3: T.S. of stomach of Clarius batrachus.
All the layers of the stomach have responded moderate to
intense with Bromophenol blue suggesting that the
occurrence of variable quantities of basic proteins.
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Int. J. Curr. Res. Biosci. Plant Biol. 2015, 2(7): 34-37
Besides the occurrence of various carbohydrates and
different proteins, the stomach of the above three fishes
elucidated the lipid nature of the stomach walls. The
presence of lipids was shown by Sudan Black B, while
copperpthalocyanin demonstrated the occurrence of
phospholipids.
Acknowledgement
Authors thank the Head, Department of Zoology,
Kakatiya University for providing necessary laboratory
facilities.
References
Agarwal, V.P., Uma Sharma, 1966. Studies on the
physiology of digestion in Nandus nandus (Ham.).
Proc. Ind. Acad. Sci. XIV(3), 157-168.
Bancroft, J.D., 1975. Histochemical Techniques.
Butterworths, London and Boston.
Blake, I.H., 1936. Studies on the comparative histology
of the digestive tube of certain teleost fishes. III. A
bottom feeding fish the sea Robin, Prionotus
carolinus. J. Morphol. 60(1), 77-102.
Dawes, B., 1929. The histology of the alimentary tract of
the plaice Pleuronectes platessa. Quart. J.
Microscop. Sci. 73, 243-247.
Dalela, R.S., 1969. Morphohistological studies of the
alimentary tract in the Mastacembel eel,
Macrognathus aculetus (BLOCH). J. Zool. Soc.
India 21, 117-128.
Ghosh, A., Das, K.M., 1987. Morphology of the
digestive tract of a mullet. Liza pasia (Ham) in
relation to its food habits. J. Indian. Soc. Coastal
Agri. Res. 5(4), 3-22.
Greene, C.W., 1912. Anatomy and histology of the
alimentary tract of the king-salmon. Bull. U. S. Bur.
Fish. 32, 777.
Gurr, E., 1974. Staining Animal Tissue: Practical
Theoretical. Leonard Hill (Books), Ltd. 631.
Humason, G.,1967. Animal tissue techniques, W. H.
Freeman and co., San Francisco and London.
Kamal Pasha, S.M., 1963.The anatomy and histology of
the alimentary canal of an omnivorous fish Mystus
(Macrones) gulio (Ham) Proc. Ind. Acad. Sci. 13,
211-221.
Kapoor, B.G., 1953. The anatomy and histology of the
alimentary canal in relation to its feeding habitats of
a ailuroid fish Wallago attu (Bl. Schn). J. Zool. Soc.
Ind. 5(2), 191-210.
Khanna, S.S., Mehrotra, B.K., 1969. Histomorphology of
the also and the stomach in some Indiaan teleosts,
with inference on their adapt features. Zool. Beitr.
14, 375-391.
Khanna, S.S., 1961. Alimentary canal in some teleostean
fishes. J. Zool. Soc. Ind. 13, 206-219.
Lillie, R.D.1965. Histopathologic Technique and
Practical Hisyochemistry. 3rd Edn. Mc Graw Hill,
New York.
McManus, J.F.A., Mowry, R.F., 1990. Stainig methods;
Histological and Histochemicl. Paul B. Boeber Inc.
Medical Division of Harper and Bros., New York.
Moitra, S.K., Ray, A.K., 1977. Morphohistology of the
alimentary canal of an Indian fresh water perch,
Celisa farciata (Bloch) in relation to food and
feeding habits. Anat. Anz. 141, 37-58.
Moitra, S.K., Ray, A.K., 1979. The comparative
morphohistology and anatomy of the digestive
system of two Indian fresh water fishes, Ambassis
nama, Ambassis ranga in relation to their food and
feeding habits. Zool. J. Anat. 102, 142-169.
Pearse, A.G.E., 1968. Histochemistry, Theoretical and
Applied. 2nd Edn. Littlle Brown and Company,
Boston, MSS.
Ray, A.K., Moitra, S.K., 1982. On the morphohistology
of the alimentary canal in the Indian climbing perch.
Amabar testredineus (Bloch) in relation to food and
feeding habits. Gegenbaurs Morph. Jhrb. Leipzing.
132, 429-441.
Sarkar, H.L., 1959. Studies on morphohistology of
digestive system in relation to the food and feeding
habits in a siluroid fish, Mystus seenghala. Proc.
Zool. Soc. Calcutta. 12(2), 97-109.
Saxena, D.B., Bakshi, F.L., 1964. Functional anatomy of
the alimentary canal of torrential stream fish Batries
birdi (Choudhori) Kashmir Soc. 1, 76-86.
Tadon, K.K., Sharma, S.C., 1968. A comparative study
of the digestive system of Channa species. Res. Bull.
Punjab. Uni. Sci. 103, 93-110.
B. Laxma Reddy and G. Benarjee (2015) / Int. J. Curr. Res. Biosci. Plant Biol. 2015, 2(7): 34-37
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